Genetic Analysis and Mapping in Bacteria and Bacteriophages

These flashcards cover key vocabulary and concepts in genetic analysis, including bacterial genetics, chromosomal mutations, and DNA structure.

Hfr

Strains of bacteria exhibiting a high frequency of recombination, capable of transferring part of their chromosome to a recipient F cell.

F+

A bacterial strain that possesses the F factor and can form a sex pilus to transfer genetic material to F- cells.

F-

A bacterial strain that lacks the F factor and cannot initiate conjugation.

Conjugation

The process by which one bacterium transfers genetic material to another through direct contact.

Plasmid

A small, circular piece of DNA that is distinct from chromosomal DNA and can replicate independently.

Transformation

A process in which a bacterium takes up small pieces of extracellular DNA from its environment.

Transduction

A virus-mediated process through which bacteriophages transfer bacterial DNA from one bacterium to another.

Nondisjunction

A cell division error where homologous chromosomes or sister chromatids fail to separate properly.

Trisomy

A genetic condition where an extra chromosome is present, leading to a total of 2n+1 chromosomes.

Monosomy

A genetic condition where a chromosome is missing, resulting in 2n-1 chromosomes.

Barr Body

An inactivated X chromosome found in the somatic cells of females, seen as a densely staining mass.

X-chromosome inactivation

The process by which one of the two X chromosomes in female mammals is randomly inactivated.

mtDNA

Mitochondrial DNA which is maternally inherited, circular, and encodes essential components for mitochondrial function.

cpDNA

Chloroplast DNA which is larger than mtDNA and is essential for photosynthesis in plants.

Semiconservative replication

Mechanism of DNA replication where each new DNA double helix contains one original strand and one new strand.

Telomere

Specialized structures at the ends of linear chromosomes that protect against degradation.

Nucleosome

A structural unit of eukaryotic chromatin consisting of a segment of DNA wound around a core of histone proteins.

Supercoiling

The overwinding or underwinding of DNA that results in a strain, leading to the formation of supercoils.

Histone

Proteins that help package and regulate DNA in eukaryotic cells, forming nucleosomes.

Gene transfer

Process during conjugation where segments of DNA are transferred from one bacterial cell to another.

Pseudoautosomal regions

Regions on the Y chromosome that share homology with the X chromosome and are crucial for pairing during meiosis.